1. Field of the Invention
The present invention relates to a computer system which is useful for designing the shapes of a plurality of products having different sizes.
2. Description of the Related Art
The profile of a tire influences the basic performance of the tire, for example, a handling stability or a ride comfort. It is necessary to determine a proper profile corresponding to the concept of the tire. Japanese Laid-Open Patent Publication No. 2002-301916 has disclosed a method of determining a tread profile using an involute function. For the determination of the profile, CAD software is used.
In order to write the size of a tire, generally, a nominal width, a nominal aspect ratio and a nominal rim diameter are used. For example, the size of a radial tire having a nominal width of 205 mm, a nominal aspect ratio of 65% and a nominal rim diameter of 15 inches is written in “205/65R15”.
There are tires designed based on the same concept and having the same brand and different sizes from each other. There are brands having several ten sizes. In many cases, the profiles of the tires having the different sizes are not analogous to each other. In the case in which the profile of a tire having a typical size is designed, a profile having another size cannot be obtained even if each dimension of the profile is simply proportional-fold. In the design of the profile, trial and error for each size are repeated. This work requires a great deal of labor.
In products other than the tire, there is a problem in that a size cannot be developed in the simple proportional times of each dimension. For example, a great deal of labor is also required for the development of a size in a golf club, golf gloves, shoes, a wear, a cap and the like.
It is an object of the present invention to provide a system capable of easily developing a size.